The present invention relates to a method for refining virgin olive oil.
The international commercial standards for olive oils (IOOC/T.15/NC nr. 1) of the International Olive Oil Council are given in OLIVAE-11nd Year-No. 8, page 9-14.
Virgin olive oil is defined according to these standards as the oil obtained from the fruit of the olive tree solely by mechanical or other physical means under conditions, particularly thermal conditions, that do not lead to alterations in the oil, and which has not undergone any treatment other than washing, decantation, centrifugation and filtration.
Virgin olive oil extra is defined as virgin olive oil of absolutely perfect flavour and odour having a maximum acidity in terms of oleic acid, of 1 g per 100 g.
Virgin olive oil fine is defined as virgin olive oil of absolutely perfect flavour and odour having a maximum acidity, in terms of oleic acid, of 1.5 g per 100 g.
Virgin olive oil semi fine is defined as virgin olive oil of good flavour and odour having a maximum acidity, in terms of oleic acid, of 3 g per 100 g, with a tolerance margin of 10% of the acidity indicated.
When virgin olive oil is stored for 24 hours at 20.degree. C., this olive oil should remain limpid.
At present a common procedure used fo refining virgin olive oil comprises the steps of:
i) adding filter aid to the virgin olive oil, for instance 25 kg filter aid (Clarcel.RTM., registered trademark) per 1000 kg virgin olive oil; PA0 ii) filtering the slurry obtained over a precoated wire-mesh leaf filter; PA0 iii) filtering the filtrate over used filter paper; and PA0 iv) filtering the paper filtered filtrate over fresh filter paper.
This conventionally used refining method requiring the use of filter aid and a multi-stage filtration treatment is cumbersome.